Sixth Mass Extinction Skeptics

As with any controversial topic there are of course skeptics. This skepticism to the idea of the sixth mass extinction have developed over the last 25 years, accusing 'doom sayers' of over-stating their case, or even worse fabricating it.

Two examples of this skepticism are the 1991 article in Science "Extinction: Are ecologists crying wolf?" and the 13/12/1993 issue of US News and World report which ran a cover story titled "The doomsday myths".

Advocates of this skepticism essentially suggest that although ecologists believe that many species are becoming extinct, or are about to become so, they do not actually know for sure.

Julian Simon from the University of Maryland is one of the most prominent anti-alarmists said in 1986 "The available facts...are not consistent with the level of concern" (Simon 1986) and in 1993 in the New York Times described claims by various ecologists that current extinction rates were equivalent to those of a mass extinction as "utterly without scientific under pinning" and "pure guesswork" (Simon 1993).

To understand this skepticism more I will focus on the 1991 Charles Mann article "Extinction: Are ecologists crying wolf?". The article opens with a quote from biologists Paul Ehrlich and E. O. Wilson who warned that biodiversity is in such danger that the US must "cease developing any more relatively undisturbed land" as a "first step to a solution". Charles Mann describes these two prominent scientists as representatives of an "exaggerated and distorted biodogma that runs the risk of impeding solutions to tropical forest deforestation" which Mann describes as a factor that all sides agree is a severe problem.

The paper states that no credible effort has been made to pin down the scientific assumptions behind the mega-extinction scenario, and that by mis-stating the problem both the credibility of science and the effort to preserve biodiversity are in danger. The paper refers to Julian Simon in the New Scientist in 1986 stating that the widely touted estimates of future extinction rates have no empirical basis whatsoever. That some scientists such as Myers envision the disappearance of 25% of the worlds species by 2100, whereas Ehrlich and Wilson conservatively figure the loss at 2-3% by 2100. Mann argues that this discrepancy calls into question the credibility of all such estimates. Wilson agrees that more data is needed, but that the imminence of the extinction problem, particularly in tropical forests is absolutely undeniable.

This skepticism has gained a number of supporters due to the fact that it is startling to imagine that humans may have caused such a large-scale tragedy. The disparity of predictions from different authorities of the scale of the imminent extinction (from 17,000 species per year to 100,000 per year) has also reduced legitimacy.

I personally feel that we need to protect as many species as we can, by acting now, and this skepticism does little to help the cause.

References

Budiansky, S. (1993). The doomsday myths. Us News and World report. 13/12/1993.
Mann, C. C. (1991). Extinction: Are ecologists crying wolf? Science. 253: 736-8.
Simon, J. (1986). Tree Data. New Scientist. 19/06/1986.
Simon, J. (1993). Before skies become entirely barren of birds; what data? New York Times. 25/05/1993.